The ability to select particular objects or features from the environment which are particularly relevant to a desired behavior is called attention, and is an emergent property of the nervous system. An understanding of the neural basis of attention will have far- reaching implications, since the selection of objects for attention involves systems for learning and memory in addition to sensory processing. Understanding the basic mechanisms in the brain which mediate attention will aid the diagnosis and treatment of mental disorders in which attentional mechanisms are affected. This project will investigate how the optic tectum may mediate auditory stimulus selection in the barn owl; specifically, do neural responses in the optic tectum of the barn owl differentiate between attended and ignored auditory targets? Previous studies of the role of the optic tectum or superior colliculus in the control of gaze have not examined the representation or selection of multiple targets, as simultaneous recordings from multiple sites of the tectum have not been feasible. In this experiment, the use of multiple, chronically-implanted electrodes will allow examination of how multiple stimuli are represented in the tectum, and whether activity related to target selection may be found therein.